[PATCH 3/5] KVM: arm64: nv: Inject SEA TTW when desc update can't write to GPA

[Oliver Upton <oupton@kernel.org>]

Similar to the handling of descriptor reads, inject an SEA during TTW
when the descriptor access fails for reasons other than a race, such as
a read-only memslot or a bad HVA.

Fixes: bff8aa213dee ("KVM: arm64: Implement HW access flag management in stage-1 SW PTW")
Fixes: e4c7dfac2f1a ("KVM: arm64: nv: Implement HW access flag management in stage-2 SW PTW")
Signed-off-by: Oliver Upton <oupton@kernel.org>
---
 arch/arm64/kvm/at.c     | 6 +++++-
 arch/arm64/kvm/nested.c | 7 ++++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c
index 9f8f0ae8e86e..119a603e636e 100644
--- a/arch/arm64/kvm/at.c
+++ b/arch/arm64/kvm/at.c
@@ -521,8 +521,12 @@ static int walk_s1(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
 		}
 
 		ret = kvm_swap_s1_desc(vcpu, ipa, desc, new_desc, wi);
-		if (ret)
+		if (ret == -EAGAIN)
 			return ret;
+		if (ret) {
+			fail_s1_walk(wr, ESR_ELx_FSC_SEA_TTW(level), false);
+			return ret;
+		}
 
 		desc = new_desc;
 	}
diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c
index d0545144eaac..f8d3f3a72328 100644
--- a/arch/arm64/kvm/nested.c
+++ b/arch/arm64/kvm/nested.c
@@ -352,8 +352,13 @@ static int walk_nested_s2_pgd(struct kvm_vcpu *vcpu, phys_addr_t ipa,
 
 	if (new_desc != desc) {
 		ret = swap_guest_s2_desc(vcpu, paddr, desc, new_desc, wi);
-		if (ret)
+		if (ret == -EAGAIN)
 			return ret;
+		if (ret) {
+			out->esr = ESR_ELx_FSC_SEA_TTW(level);
+			out->desc = desc;
+			return 1;
+		}
 
 		desc = new_desc;
 	}
-- 
2.47.3